1. Field of the Invention
The present invention relates to a tool changer for use with a machine tool having a spindle device, such as a tapping machine, a drilling machine, or the like.
2. Description of the Relevant Art
Tapping machines and drilling machines equipped with spindle devices are required to change tools when different workpiece types are to be machined.
Japanese Laid-Open Patent Publication No. 61-44546 discloses a tool changer for use with a machine tool having a spindle device, the tool changer having a tool changing arm disposed between a tool magazine storing a number of different tools and the spindle device, and having chucking units on its opposite ends. For changing tools, the tool changing arm and the spindle device are moved in unison along parallel paths toward the tool magazines, and tools are gripped by the respective chucking units on the tool changing arm, which is then turned 180.degree. to change the tools.
With the conventional tool changer, however, since the entire tool changer and the spindle device have to be moved in a parallel manner toward the tool magazine, a relatively large driving mechanism is required for moving the tool changer and the spindle device. Other drive sources for rotating the tool changing arm, moving the tool changing arm back and forth, and moving the tool changer as a whole are also needed For this reason, the overall machine setup is large in size, heavy, and requires complex control modes for controlling movement of the various components.